Wheel covers are common on cars, in part because the wheel rims provide a reliable mechanism for attachment and in part because car owners generally do not need to frequently access the lug nuts or other components covered by a hub cap.
In contrast, wheel covers for large vehicles such as semis are rarely used. Neither dual-wheels nor single-wide wheels are configured so that a wheel cover can be snapped into engagement as in the case with many passenger car wheel/wheel disk arrangements. Instead, dual wheels and single-wide wheels, especially on tractor-trailer vehicles and other large vehicles, are characterized by the substantial depth from the plane of the outer wheel rim inward to the region of the wheel hub where the wheel is attached to a brake drum, axle rotor, additional wheel or the like. This characteristic makes it difficult to secure a wheel cover to a dual wheel or single-wide wheel. Furthermore, a driver, mechanic or operator may need to inspect or access a hub odometer, an oil reservoir gauge, lug nuts, tire inflation valve, or some other component.
Some prior art systems and devices include rigid wheel covers. A disk, manufactured from aluminum or some other metal, is secured to a bracket using screws, bolts, or other hardware. A drawback to this type of wheel cover is the rigid disk is easily damaged by contact with a curb, post, or other traffic device. The time required to install and remove the cover, and the likelihood of a rigid cover rattling, making noise, and coming loose are also disadvantages. Some prior art methods involve installing a frame and then attaching (such as by using a zipper) a fabric shield to the frame. In operation, prior art approaches using a zipper typically utilize the inner bead or “drop-center” of the wheel. As such, prior art wheel covers may touch the outer flange but effectively “grabs” inside. A drawback is that this type of wheel cover does not fit all types of wheels, such as single-wide wheels, and requires the wheels to be cleaned when they may be heavily soiled and difficult to clean.
Some prior art methods of attaching a wheel cover to a truck wheel include a hub feature, such as a mounting bracket, that projects outwardly from the end of the wheel hub approximately to the plane of the wheel rim. However, these attachment methods require tools and significant labor for installation or removal, which is necessary to perform most repairs or maintenance on the wheels.
Some prior art methods include a peripheral mounting method in which clips or other means attach a wheel cover to the outer flange of the wheel rim. However, attachment brackets which rely on hooks or spring clips are susceptible to loosening under stress and are difficult to install. Furthermore, prior art methods of mounting wheel covers to the periphery of the wheel have shortcomings due to the difficulty of rigidly attaching a clip or other mounting feature to the outer wheel rim or flange. Further, the depth from the plane of the outer wheel rim inward to the region of the wheel hub where the inner diameter of the wheel is larger than elsewhere is typically several inches on dual wheels and single-wide wheels. As a result, these wheels cannot accommodate a wheel cover that can normally be snapped into engagement with the wheel outer flange (as in the case with many passenger car wheel/wheel disk arrangements, where conventional hub caps are used).
Furthermore, many of the prior art attachment systems are undesirably complex, either in the number of components required and/or the labor needed for installation and removal. The manufacturing costs of systems having a large number of components can be prohibitive.
Many prior art wheel covers are constructed of a solid surface with no openings to allow for ventilation that may assist to cool the hub area and adjacent brake components or to provide an exit means for water and debris.